Image forming apparatus and image forming method

ABSTRACT

An image forming apparatus includes an image forming unit configured to perform a printing process of forming an image on a print medium based on print data, and a processor. The processor is configured to determine whether or not the printing process has completed based on remaining print data to be printed, when the print medium is removed from a paper discharge tray in which the print medium on which the image is formed by the image forming unit is placed, and to cause a warning to be output upon determining that the printing process has not completed based on the remaining print data to be printed.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority fromJapanese Patent Application No. 2017-045841, filed Mar. 10, 2017, theentire contents of which are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to an image formingapparatus and an image forming method.

BACKGROUND

In the related art, an image forming apparatus performs printing inresponse to a print request. The image forming apparatus forms an imageon a print medium (e.g., sheet) such as a paper, and discharges theprint medium on which the image is formed onto a paper discharge tray.The image forming apparatus includes a conveying unit that conveys theprint medium and an image forming unit that forms the image on theconveyed sheet.

The image forming apparatus sometimes stops a printing process offorming an image on the print medium due to various factors such as outof paper, out of toner, the occurrence of a jam, and image stabilizationprocessing. When the printing process stops, the image forming apparatusperforms a warning display on a display unit, and thereby notifies auser that the printing process has not completed.

However, there is a problem that the user does not recognize the warningdisplay and thus the user may take the print medium discharged onto thepaper discharge tray.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram for explaining a configuration example of an imageforming apparatus according to an embodiment.

FIG. 2 is a diagram for explaining a configuration example of the imageforming apparatus.

FIG. 3 is a diagram for explaining a configuration example of the imageforming apparatus.

FIG. 4 is a flowchart depicting an operation example of the imageforming apparatus.

FIG. 5 is a flowchart depicting an operation example of the imageforming apparatus.

FIG. 6 is a diagram for explaining a configuration example of an imageforming apparatus according to another embodiment.

DETAILED DESCRIPTION

According to one embodiment, there is provided an image formingapparatus including an image forming unit configured to perform aprinting process of forming an image on a print medium based on printdata, and a processor. The processor is configured to determine whetheror not the printing process has completed based on remaining print datato be printed, when the print medium is removed from a paper dischargetray in which the print medium on which the image is formed by the imageforming unit is placed, and to cause a warning to be output upondetermining that the printing process has not completed based on theremaining print data to be printed.

Hereinafter, an image forming apparatus and an image forming methodaccording to an embodiment will be described with reference to thedrawings.

FIG. 1 is an explanation diagram illustrating a configuration example ofan image forming apparatus 1 according to the embodiment. FIG. 2 is ablock diagram illustrating a function provided in the image formingapparatus 1 as a block.

For example, the image forming apparatus 1 is a multifunction peripheral(MFP) that performs various processes such as image formation whileconveying a recording medium such as a print medium. For example, theimage forming apparatus 1 is a solid-state scanning type printer (forexample, LED printer) that scans a LED array performing variousprocesses such as image formation while conveying the recording mediumsuch as the print medium. In addition, the image forming apparatus 1 maybe an ink jet type printer (ink jet printer) that scans ink jet headsthat ejects ink or may be another type printer. In the embodiment, it isassumed that the image forming apparatus 1 is a LED printer.

The image forming apparatus 1 irradiates a photoconductive drum withlight corresponding to image data for printing by charging thephotoconductive drum so as to form a latent image (e.g., electrostaticlatent image) on the photoconductive drum. The image forming apparatus 1attaches a toner to the latent image formed on the photoconductive drum,and transfers the toner attached to the latent image onto the printmedium. In addition, the image forming apparatus 1 nips the print mediumon which the toner image is transferred between fixing rollers heated toa predetermined temperature by a heater, and fixes the toner image tothe print medium.

In addition, the image forming apparatus 1 forms an image of a printmedium using light which is reflected after having been irradiated onthe print medium. The reflected light is focused on an image sensorwhich converts charge accumulated in the image sensor into a digitalsignal to be read.

The image forming apparatus 1 includes a housing 11, a document platen12, a scanner unit 13, an automatic document feeder (ADF) 14, a sheetfeeding cassette 15, a paper discharge tray 16, an image forming unit17, a conveying unit 18, a main control unit 19, a display unit 20, anoperation I/F 21, a communication I/F 22, a camera 23, a speaker 24, acard reader 25, and a sensor 26.

The housing 11 is the main body holding the document platen 12, thescanner unit 13, the ADF 14, the sheet feeding cassette 15, the paperdischarge tray 16, the image forming unit 17, the conveying unit 18, themain control unit 19, the display unit 20, the operation I/F 21, thecommunication I/F 22, the camera 23, the speaker 24, the card reader 25,and the sensor 26 therein.

The document platen 12 is a portion on which a print medium P as anoriginal document to be read is placed. The document platen 12 includesa glass plate 31 having a placement surface 32 on which the print mediumP as the original document is placed and a space 33 located on theopposite side of the placement surface 32 of the glass plate 31.

The ADF 14 is a mechanism for conveying the print medium P along a sheetconveying path thereof. The ADF 14 is located on the upper surface sideof the document platen 12 so as to be able to be opened and closed. TheADF 14 picks up the print medium P placed on a tray thereof and conveysthe print medium P while the print medium P comes into close contactwith the placement surface 32 of the glass plate 31 according to thecontrol of the main control unit 19.

The scanner unit 13 reads an image on the surface of the print medium Paccording to the control of the main control unit 19. The scanner unit13 is disposed in the space 33 of the document platen 12. The scannerunit 13 includes an image sensor, an optical element, a light device, orthe like.

The image sensor is an imaging element in which pixels for convertinglight into an electrical image signal are arranged in a line manner. Forexample, the image sensor is configured by a charge coupled device(CCD), a complementary metal oxide semiconductor (CMOS), or anotherimaging element.

The optical element is an element for focusing an image of light from apredetermined read range on pixels of the image sensor. The read rangeof the optical element is a region of the line shape on the placementsurface 32 of the document platen 12. An image of light reflected by theprint medium P placed on the placement surface 32 and transmittedthrough the glass plate 31 is input into the optical element. Theoptical element focuses the input image of light on the pixels of theimage sensor.

The light device irradiates the print medium P with light. The lightdevice includes a light source and a light guide member for irradiatingthe print medium P with light from the light source. The light deviceirradiates the light emitted from the light source to a region includingthe read range of the optical element by the light guide member.

In order to read the surface of the print medium P placed on theplacement surface 32, the scanner unit 13 is driven by a drivingmechanism (not illustrated) in a sub-scanning direction which isorthogonal to the arrangement direction (i.e., main scanning direction)of the pixels of the image sensor and parallel to the placement surface32. The scanner unit 13 is driven in the sub-scanning direction, andcontinuously reads an images line by line using the image sensor, andthere by obtains overall image data of the print medium P placed on theplacement surface 32.

In addition, when the print medium P is conveyed by the ADF 14, thescanner unit 13 is located at a position facing a position where theprint medium P comes into close contact with the placement surface 32.The scanner unit 13 continuously reads images line by line using theimage sensor from the print medium P conveyed by the ADF 14, and therebyobtains the overall image data of the print medium P conveyed by the ADF14 (original document image data).

The sheet feeding cassette 15 is a cassette configured to accommodatethe print medium P. The print medium P is supplied to the sheet feedingcassette 15 from an outside of the housing 11. For example, the sheetfeeding cassette 15 is configured to be pulled out from the housing 11.

The paper discharge tray 16 is a tray to receive the print medium Pdischarged from the conveying unit 18. In addition, the sensor 26, whichwill be described below, is located in the paper discharge tray 16.

The image forming unit 17 forms an image on the print medium P based onthe control of the main control unit 19. For example, the image formingunit 17 charges an outer circumferential surface of a drum, forms thelatent image according to the image data for printing on the chargedsurface of the drum, attaches a toner to the latent image formed on thedrum, and transfers the toner attached to the latent image onto theprint medium P, and thereby fixes the toner image to the print medium P.For example, as illustrated in FIG. 1, the image forming unit 17includes a drum 41, an exposure unit 42, a developing device 43, atransfer belt 44, a pair of transfer rollers 45, and a pair of fixingrollers 46.

The drum 41 is a cylindrical photoconductive drum. The drum 41 isprovided so as to be in contact with the outer circumferential surfaceof the transfer belt 44 which has an endless shape. The outercircumferential surface of the drum 41 is uniformly charged by a charger(not illustrated). In addition, the drum 41 rotates at a constant speedby the driving mechanism (not illustrated).

The exposure unit 42 forms an electrostatic latent image on the outercircumferential surface of the charged drum 41. The exposure unit 42forms the electrostatic latent image on the outer circumferentialsurface of the drum 41 by irradiating a surface of the drum 41 with alaser beam from a light emitting element or the like according to theprint data. The exposure unit 42 includes a light emitting unit and theoptical element.

The light emitting unit includes a configuration (for example, LEDarray) in which the light emitting elements that emit light according tothe electric signal (i.e., image signal) are arranged in a line manner.The light emitting element of the light emitting unit emits light of awavelength which can form the latent image on the charged drum 41. Thelight emitted from the light emitting unit is focused as an image on thesurface of the drum 41 by the optical element.

The developing device 43 attaches a toner (i.e., developer) to theelectrostatic latent image formed on the drum 41. With this, thedeveloping device 43 forms an image of the toner on the surface of thedrum 41.

For example, the drum 41, the exposure unit 42, and the developingdevice 43 of the image forming unit 17 are respectively provided foreach different color such as cyan, magenta, yellow, and black. In thiscase, each of a plurality of developing devices 43 holds the toner ofdifferent colors.

The transfer belt 44 is an endless member for receiving the toner imageformed on the surface of the drum 41, and for transferring the tonerimage to the print medium P. The transfer belt 44 is rotated by rotationof a roller. The transfer belt 44 receives the toner image formed on thedrum 41 at a position in contact with the drum 41, and transfers thereceived toner image to a print medium P which is sandwiched andconveyed by the transfer belt 44 and one of the pair of transfer rollers45.

The pair of transfer rollers 45 is configured to nip the transfer belt44. The pair of transfer rollers 45 transfers the toner image on thetransfer belt 44 to the print medium P.

The pair of fixing rollers 46 is configured to nip the print medium P.The pair of fixing rollers 46 is heated by a heater (not illustrated).The pair of fixing rollers 46 fixes the toner image formed on the printmedium P by applying pressure and heat to the nipped print medium P.That is, the pair of fixing rollers 46 fixes an image onto the printmedium P.

The conveying unit 18 conveys the print medium P. The conveying unit 18includes a conveying path configured by a plurality of guides and aplurality of rollers, and a sensor that detects a conveyed position ofthe print medium P on the conveying path. The conveying path is a pathto convey the print medium P. A conveying roller rotates by a motoroperated based on the control of the main control unit 19, and therebyconveys the print medium P along the conveying path. In addition, someguides (e.g., flappers) among the plurality of guides rotate by a motoroperated based on the control of the main control unit 19, and therebyswitch the conveying path conveying the print medium P.

For example, as illustrated in FIG. 1, the conveying unit 18 includes apick-up roller 51, a paper feed conveying path 52, a paper dischargeconveying path 53, and a reverse conveying path 54.

The pick-up roller 51 picks up the print medium P accommodated in thesheet feeding cassette 15 and feeds the picked up print medium P to thepaper feed conveying path 52.

The paper feed conveying path 52 is the conveying path for conveying theprint medium P picked up from the sheet feeding cassette 15 by thepick-up roller 51 to the image forming unit 17.

The paper discharge conveying path 53 is the conveying path fordischarging the print medium P on which an image is formed by the imageforming unit 17 from the housing 11. The print medium P dischargedthrough the paper discharge conveying path 53 is discharged to the paperdischarge tray 16.

The reverse conveying path 54 is the conveying path for supplying theprint medium P to the image forming unit 17 again in a state where thefront and back sides and the leading and trailing edges of the printmedium P on which the image is formed by the image forming unit 17 arereversed.

The main control unit 19 controls the image forming apparatus 1. Themain control unit 19 includes, for example, a CPU 61, a ROM 62, a RAM63, and a nonvolatile memory 64.

The CPU 61 is a processor. The CPU 61 performs various processes basedon data such as a program stored in the ROM 62. The CPU 61 executes theprogram stored in the ROM 62, and thereby functions as a control unitwhich can perform various operations. Each of the functions of the maincontrol unit 19 can be also realized by control circuit, ASIC, or acombination thereof.

The ROM 62 is a read-only nonvolatile memory. The ROM 62 stores theprogram and data or the like used in the program.

The RAM 63 is a volatile memory that functions as a working memory. TheRAM 63 temporarily stores data or the like under processing of the CPU61. In addition, the RAM 63 temporarily stores the program executed bythe CPU 61.

The nonvolatile memory 64 is a storage medium which can store varioustypes of information. The nonvolatile memory 64 stores the program anddata or the like used in the program. For example, the nonvolatilememory 64 is a solid state drive (SSD), a hard disk drive (HDD), oranother storage device. Instead of the nonvolatile memory 64, a memoryI/F such as a card slot into which the storage medium such as a memorycard can be inserted may be provided.

The display unit 20 includes a display that displays a screen accordingto a video signal input from the main control unit 19 or a displaycontrol unit such as a graphic controller (not illustrated). Forexample, a screen for various settings of the image forming apparatus 1is displayed on a display of the display unit 20.

The operation I/F 21 is connected to an operation member (notillustrate). The operation I/F 21 supplies an operation signal inresponse to an operation of the operation member to the main controlunit 19. For example, the operation member is a touch sensor, a numerickeypad, a power key, a paper feed key, various function keys, akeyboard, or the like. For example, the touch sensor is a resistivetouch sensor, a capacitive touch sensor, or the like. The touch sensorobtains information indicating a position designated by the user in aregion. The touch sensor is configured as a touch panel being integratedwith the display unit 20, and inputs a signal indicating a positiontouched by the user on the screen displayed on the display unit 20 tothe main control unit 19.

The communication I/F 22 is an interface for communicating with anotherdevice. For example, the communication I/F 22 is used for communicationwith a host device (external device) that transmits print data to theimage forming apparatus 1. For example, the communication I/F 22 isconfigured as a LAN connector. In addition, the communication I/F 22 mayperform wireless communication with another device according to atelecommunications standard such as Bluetooth (registered trademark) andWi-fi (registered trademark).

The camera 23 captures a face of a person who operates the image formingapparatus 1. The camera 23 includes, for example, an image sensor, anoptical element, or the like.

The image sensor is the imaging element in which pixels for convertinglight into the electric image signal are arranged in the line manner.For example, the image sensor is configured by the CCD, the CMOS, oranother imaging element.

The optical element focuses an image of light from a predetermined readrange on the pixels of the image sensor. The read range of the opticalelement is a predetermined range in the vicinity of the image formingapparatus 1 and is a range in which it is assumed that the face of theuser operating the image forming apparatus 1 is viewed.

The speaker 24 outputs audio in response to an audio signal input fromthe main control unit 19. For example, the speaker 24 generates alertsound with respect to the user operating the image forming apparatus 1.

The card reader 25 is an interface for communicating with an IC cardheld by the user of the image forming apparatus 1. The card reader 25performs transmission and reception of data with the IC card throughcontact communication or noncontact communication.

The IC card includes an IC chip and a communication circuit. The IC chipincludes a processor, a ROM, a RAM, a nonvolatile memory, and the like.The nonvolatile memory of the IC chip has identification informationindicating the user holding the IC card. For example, the communicationcircuit is configured as an antenna or a contact terminal (contactpattern). The communication circuit is electrically or magneticallyconnected to the card reader 25.

The card reader 25 communicates with the IC card, and thereby obtainsthe identification information corresponding to the user holding the ICcard, from the IC card.

The sensor 26 is a sensor that detects whether or not the print medium Phas been placed on the paper discharge tray 16. FIG. 3 is an explanationdiagram for explaining a configuration in the vicinity of the paperdischarge tray 16 of the image forming apparatus 1. The sensor 26 has adriving member stood up by an elastic member. The driving member islocated at a position in contact with the lower surface of the printmedium P discharged onto the paper discharge tray 16, and pressed downby the weight of the print medium P discharged onto the paper dischargetray 16. The sensor 26 supplies a signal indicating OFF to the CPU 61 ina state where the driving member stands up and supplies a signalindicating ON to the CPU 61 in a state in which the driving member ispressed down by the print medium P discharged onto the paper dischargetray.

Next, various operations performed by the CPU 61 will be described.

The CPU 61 executes the program stored in the ROM 62, and therebyfunctions as an obtaining unit that obtains the print data for formingan image on the print medium P. For example, the CPU 61 receives theprint data from the external device through the communication I/F 22which will be described below. In addition, the CPU 61 may be configuredto generate the print data based on an image obtained by the scannerunit 13.

The print data may be data for forming an image on one print medium P,or may be data for forming an image on a plurality of print media P. Inaddition, the print data may be data including a designation of numbersof copies for repeatedly printing the same contents.

In addition, the CPU 61 executes the program stored in the ROM 62, andthereby performs a printing process for forming an image on the printmedium P corresponding to the print data by the image forming unit 17.For example, the CPU 61 inputs the print data to the image forming unit17, inputs a transport control signal of instructing the conveyance ofthe print medium P to the conveying unit 18, and thereby forms an imageon a surface of the print medium P while conveying the print medium Pthrough the image forming unit 17.

In addition, the CPU 61 executes the program stored in the ROM 62, andthereby functions as a determination unit that determines whether or notthe print medium P has been removed from the paper discharge tray 16 inthe case where the print medium P on which an image is formed by theimage forming unit 17 is placed on the paper discharge tray 16.

The CPU 61 determines whether or not the print medium P on which theimage is formed is placed on the paper discharge tray 16 based on asignal from the sensor 26. For example, when a detected result of thesensor 26 is ON, the CPU 61 determines that the print medium P is placedon the paper discharge tray 16. On the other hand, when the detectedresult of the sensor 26 is OFF, the CPU 61 determines that the printmedium P is not placed on the paper discharge tray 16.

Furthermore, the CPU 61 determines whether or not the print medium P hasbeen removed from the paper discharge tray 16 based on the signal fromthe sensor 26. For example, when the detected result of the sensor 26 ischanged from ON to OFF, the CPU 61 determines that the print medium Pthat was on the paper discharge tray 16 has been removed from the paperdischarge tray 16. With this, the CPU 61 determines whether or not theprint medium P has been removed from the paper discharge tray 16.

In addition, when the print medium P is removed from the paper dischargetray 16, the CPU 61 determines whether or not the printing process hascompleted based on the print data. When the print medium P is removedfrom the paper discharge tray 16, if the printing process based on theprint data has not completed, the CPU 61 functions as a notifying unitthat outputs a warning through the display unit 20 and/or the speaker24.

For example, when the print medium P is removed from the paper dischargetray 16 and an operation of the image forming unit 17 is interrupted,the CPU 61 determines that the printing process has not completed. Inaddition, for example, when the print medium P is removed from the paperdischarge tray 16 and printing of all pages indicated by the print datahas not completed, the CPU 61 determines that the printing process hasnot completed. In addition, for example, when the print medium P isremoved from the paper discharge tray 16 and printing of all copiesindicated by the print data has not completed, the CPU 61 determinesthat the printing process has not completed. In addition, for example,when the print medium P is removed from the paper discharge tray 16 andoverall printing based on a plurality of pieces of print data has notcompleted, the CPU 61 determines that the printing process has notcompleted.

Next, the printing process in the image forming apparatus 1 will bedescribed.

FIG. 4 is a flowchart depicting the printing process in the imageforming apparatus 1.

The CPU 61 of the image forming apparatus 1 obtains the print data (Act11). For example, the CPU 61 receives the print data from the externaldevice through the communication I/F 22. In addition, the CPU 61 may beconfigured to generate the print data based on an image obtained by thescanner unit 13.

The print data may be data for forming an image on one print medium P,and data for forming an image on the plurality of print media P. Inaddition, the print data may be data including the designation of numberof copies for printing the same contents.

The CPU 61 starts the printing process based on the print data when theprint data is obtained. First, the CPU 61 recognizes numbers (number ofpages) of the print media to be printed based on the print data (Act12). Next, the CPU 61 recognizes the number of copies to be printedbased on the print data (Act 13).

The CPU 61 forms an image on one print medium P based on the print data(Act 14). That is, the CPU 61 controls the conveying unit 18 to pick-upthe print medium P from the sheet feeding cassette 15 and conveys theprint medium P to the image forming unit 17. Furthermore, the CPU 61controls the image forming unit 17, and thereby causes to form an imageon the print medium P according to the print data. Furthermore, the CPU61 controls the conveying unit 18, and thereby causes to discharge theprint medium P on which an image is formed by the image forming unit 17onto the paper discharge tray 16.

The CPU 61 determines whether or not an interruption of the printingprocess has occurred (Act 15). For example, the CPU 61 sequentiallydetermines whether or not the out of the sheet occurs, the out of thetoner occurs, the jam occurs, and an image stabilization process isbeing performed. When the out of the sheet occurs, the out of the toneroccurs, the jam occurs, or the image stabilization process is beingperformed, the CPU 61 determines that the interruption of the printingprocess has occurred.

For example, the CPU 61 determines whether or not the out of the sheetoccurs based on a detected result of a sensor (not illustrated)installed in the sheet feeding cassette 15. In addition, for example,the CPU 61 determines whether or not the out of the toner occurs basedon a detected result of a sensor (not illustrated) installed in thedeveloping device 43. In addition, for example, the CPU 61 determineswhether or not a jam of a state where the print medium P is jammed onthe conveying path and not conveyed, occurs, based on a detected resultof a sensor (not illustrated) arranged along the conveying path of theconveying unit 18. In addition, for example, the CPU 61 determineswhether or not the image stabilization process which is a process ofadjusting the toner density of the toner image, a position in which thetoner image is formed, or the like, is being performed in the imageforming unit 17.

When the out of the sheet occurs, the out of the toner occurs, the jamoccurs, or the image stabilization process is being performed, the CPU61 interrupts the printing process. In addition, when the cause of theinterruption of the printing process is solved, the CPU 61 restarts theinterrupted printing process. That is, when the paper is replenished,the toner is replenished, the jammed print medium P is removed, or theimage stabilization process has completed, the CPU 61 restarts theinterrupted printing process.

When the interruption of the printing process occurs (Act 15, Yes), theCPU 61 performs a first notification process according to which thewarning to be output (Act 16). For example, the CPU 61 causes thedisplay unit 20 to display information corresponding to the cause of theinterruption of the printing process, and thereby notifies a user thatthe printing process is interrupted. When it is determined that theinterruption of the printing process does not occur in Act 15 (Act 15,No), the CPU 61 transitions to a process of Act 17.

The CPU 61 determines whether or not printing of all pages has completed(Act 17). For example, the CPU 61 counts the number of printed pagesevery time printing of one page has completed, and when the countedvalue reaches the number of pages recognized in ACT 12, the CPU 61determines that the printing of all pages has completed. When it isdetermined that the printing of all pages has not completed (Act 17,No), the CPU 61 transitions to a process of Act 14. In addition, when itis determined that the printing of all pages has completed (Act 17,Yes), the CPU 61 transitions to a process of Act 18.

The CPU 61 determines whether or not the printing of all copies hascompleted (Act 18). For example, the CPU 61 counts the number of sheetsof which printing has completed every time the printing of each copy(per page set) has completed, and when the counted number reaches thenumber of sheets recognized in Act 13, the CPU 61 determines that theprinting of all copies has completed. When it is determined that theprinting of all copies has not completed (Act 18, No), the CPU 61transitions to a process of Act 14.

In addition, when it is determined that the printing of all copies hascompleted (Act 18, Yes), the CPU 61 determines that the printing processhas completed based on the print data obtained in Act 11 (Act 19), andends the process. When the CPU 61 received new print data in processesof Act 11 to Act 19, the CPU 61 may be configured to perform processesof Act 12 to Act 19 by transitioning the process to Act 12.

In addition, the CPU 61 may be configured to store flag informationindicating whether the printing process has completed, in thenonvolatile memory 64. When the print data is obtained in Act 11, theCPU 61 rewrites the flag information to a state indicating that theprinting process has not completed. In addition, when it is determinedthat the printing process has completed in Act 19, the CPU 61 rewritesthe flag information to a state indicating that the printing process hascompleted.

FIG. 5 is a flowchart depicting a process at the time of removing theprint medium P from the paper discharge tray 16 of the image formingapparatus 1. The CPU 61 of the image forming apparatus 1 performs aprocess illustrated in FIG. 5 in parallel with the printing processillustrated in FIG. 4.

The CPU 61 determines whether or not the print medium P on which animage is formed is placed on the paper discharge tray 16 (Act 21). Forexample, when a detected result of the sensor 26 is ON, the CPU 61determines that the print medium P is placed on the paper discharge tray16. In addition, for example, when the detected result of the sensor 26is OFF, the CPU 61 determines that the print medium P is not placed onthe paper discharge tray 16.

When it is determined that the print medium P is not placed on the paperdischarge tray 16 (Act 21, No), the CPU 61 performs the determination ofAct 21 again.

When it is determined that the print medium P is placed on the paperdischarge tray 16 (Act 21, Yes), the CPU 61 determines whether or notthe print medium P on the paper discharge tray 16 is removed (Act 22).For example, when the detected result of the sensor 26 is changed fromON to OFF, the CPU 61 determines that the print medium P on the paperdischarge tray 16 has been removed.

When it is determined that the print medium P on the paper dischargetray 16 has not been removed (Act 22, No), the CPU 61 performs thedetermination of Act 22 again.

When it is determined that the print medium P on the paper dischargetray 16 has been removed (Act 22, Yes), the CPU 61 determines whether ornot the printing process is completed (Act 23). For example, when theinterruption of the printing process occurs, the CPU 61 determines thatthe printing process has not completed. That is, when the out of thesheet occurs, the out of the toner occurs, the jam occurs, or the imagestabilization process is being performed, the CPU 61 determines that theprinting process has not completed. In addition, for example, when theprinting of all pages based on the print data has not completed, the CPU61 determines that the printing process has not completed. In addition,for example, when the printing of all copies based on the print data hasnot completed, the CPU 61 determines that the printing process has notcompleted. In other words, when both of the printing of all copies andthe printing of all pages based on the print data are completed withoutoccurring the interruption of the printing process, the CPU 61determines that the printing process has completed.

In addition, a configuration in which when the flag information storedin the nonvolatile memory 64 is sequentially rewritten according towhether or not the printing process has completed, the CPU 61 determineswhether or not the printing process has completed based on the flaginformation stored in the nonvolatile memory 64, may be implemented.That is, when the flag information stored in the nonvolatile memory 64indicates that the printing process has completed, the CPU 61 determinesthat the printing process has completed. On the other hand, when theflag information stored in the nonvolatile memory 64 indicates that theprinting process has not completed, the CPU 61 determines that theprinting process has not completed.

When it is determined that the printing process has completed (Act 23,Yes), the CPU 61 ends a process in FIG. 5 without performing theprocess.

In addition, when it is determined that the printing process has notcompleted (Act 23, No), the CPU 61 performs a second notificationprocess that according to which the warning is output (Act 24), and endsthe process of FIG. 5. For example, the CPU 61 causes the speaker 24 togenerate a predetermined warning sound, and thereby causes the warningto be output to the user. In addition, for example, the CPU 61 displaysinformation indicating the print data of which printing process has notcompleted, on the display unit 20, and thereby causes the warning to beoutput. Furthermore, the CPU 61 may urge a user's attention by blinkingthe display on the display unit 20, changing color, or the like. Withthis, the CPU 61 can notify the user that the printing process has notcompleted, that is, the print medium P which is not yet dischargedexists.

The CPU 61 performs the second notification process by a methoddifferent from the first notification process, and thereby can urgeattention to remember to take out the print medium P to the user.Specifically, the CPU 61 sets a display screen, the warning sound, orthe like in the second notification process different from those of thefirst notification process, and thereby can urge the attention toremember to take out the print medium P, which is not yet printed out,to the user.

According to the above configuration, the image forming apparatus 1includes the image forming unit 17 that forms an image on the printmedium P based on the print data, and the CPU 61. The image formingapparatus 1 discharges the print medium P on which an image is formed bythe image forming unit 17, to the paper discharge tray 16. When theprint medium P is removed from the paper discharge tray 16, the CPU 61of the image forming apparatus 1 determines whether or not the printingprocess based on the print data has completed. When it is determinedthat the printing process based on the print data has not completed, theCPU 61 causes the warning to be output. According to this configuration,when the printing process based on the print data has not completed,that is, when an undischarged print medium P exists, the image formingapparatus 1 outputs the warning at a timing at which the print medium Phas been removed from the paper discharge tray 16. With this, the imageforming apparatus 1 can effectively notify the user that theundischarged print medium P exists. As a result, it is possible toprevent the user from forgetting to take out the print medium P from theimage forming apparatus 1.

In addition, when the operation of the image forming unit 17 isinterrupted, the CPU 61 determines that the printing process has notcompleted. For example, when the out of the sheet occurs, the out of thetoner occurs, the jam occurs, or the image stabilization process isbeing performed, the CPU 61 determines that the printing processing hasnot completed. With this, the image forming apparatus 1 can effectivelynotify the user that the undischarged print medium P exists. As aresult, it is possible to prevent the user from forgetting to take outthe print medium P, which is not yet printed out, from the image formingapparatus 1.

In addition, when the print data is data for instructing performance ofthe plurality of copies in printing processes, the CPU 61 determineswhether or not the printing process of all copies indicated by the printdata has completed. When the printing process of all copies has notcompleted, the CPU 61 causes a warning to be output at a timing when theprint medium P is removed from the paper discharge tray 16. With this,the image forming apparatus 1 can effectively notify a user that theundischarged print medium P exists. As a result, it is possible toprevent the user from forgetting to take out the print medium P from theimage forming apparatus 1.

In the above-described embodiment, a configuration in which when theoperation of the image forming unit 17 is interrupted, when the printingof all pages has not completed, or when the printing process of allcopies has not completed, the image forming apparatus 1 outputs thewarning at the timing when the print medium P is removed from the paperdischarge tray 16, is described. However, the embodiment is not limitedto the above example. When a plurality of the print data is obtained,the image forming apparatus 1 may determine whether or not the printingprocess based on the plurality of pieces of print data has completed.Furthermore, a configuration in which when the printing process based onthe plurality of pieces of print data has not completed, the imageforming apparatus 1 outputs the warning at the timing when the printmedium P is removed from the paper discharge tray 16 may be implemented.As a result, when a user transmits a plurality of print instructions tothe image forming apparatus 1, it is possible to prevent the user fromforgetting to take out the print medium P from the image formingapparatus 1.

In the above-described embodiment, the CPU 61 determines whether or notthe print medium P on the paper discharge tray 16 is removed in Act 22,and if it is determined that the print medium P on the paper dischargetray 16 is removed, the CPU 61 determines whether or not the printingprocess has completed in Act 23. However, the embodiment is not limitedto the above configuration. A configuration in which the CPU 61sequentially performs a process of Act 22 and a process of Act 23 inreverse order, may be implemented. That is, a configuration in which theCPU 61 determines whether or not the printing process has completed,when it is determined that the printing process has not completed, theCPU 61 determines whether or not the print medium P on the paperdischarge tray 16 is removed, and when it is determined that the printmedium P on the paper discharge tray 16 is removed, the CPU 61 performsthe second notification process, may be implemented.

In the above-described embodiment, a configuration in which the sensor26 is a sensor that detects whether or not the print medium P isdischarged on the paper discharge tray 16, is described. However, theembodiment is not limited to the configuration. A configuration in whichthe sensor 26 detects the weight of the print medium P discharged on thepaper discharge tray 16, may be implemented. When the sensor 26 isconfigured to detect the weight of the print medium P discharged on thepaper discharge tray 16, the CPU 61 can determine whether or not theprint medium P has been removed from the paper discharge tray 16 basedon the weight detected by the sensor 26. Specifically, when the weightdetected by the sensor 26 decreases, the CPU 61 determines that theprint medium P has been removed from the paper discharge tray 16.According to the configuration, the CPU 61 can determine that a part ofthe plurality of print media P discharged on the paper discharge tray 16has been removed from the paper discharge tray 16.

In addition, in the above-described embodiment, a configuration in whichthe image forming apparatus 1 determines whether or not the printing hascompleted when the print medium P is removed from the paper dischargetray 16 of the image forming apparatus 1, is described. However, theembodiment is not limited to the configuration. A configuration inwhich, in a case where a finisher that bundles and seals a plurality ofprint media P is connected to the image forming apparatus 1, the imageforming apparatus 1 determines whether or not the printing has completedat the time of removing a bundle of the print media P from a tray fromwhich the bundled print media Pare discharged, may be implemented. Inthis case, the finisher includes a sensor for detecting that the bundleof the print media P has been removed from the tray configured todischarge the bundled print media P. The finisher supplies a signal fromthe sensor to the image forming apparatus 1. The image forming apparatus1 determines whether or not the bundle of the print media P has beenremoved from the finisher according to the signal from the sensor of thefinisher.

In the above-described embodiment, a configuration in which the sensor26 supplies the signal indicating whether or not the print medium P isdischarged on the paper discharge tray 16 to the CPU 61 according to theweight of the print medium P discharged to the paper discharge tray 16,is described. However, the embodiment is not limited to theconfiguration. A configuration in which the image forming apparatus 1includes a sensor optically detecting whether or not the print medium Pis discharged on the paper discharge tray 16, may be implemented.

In addition, a configuration in which the image forming apparatus 1includes a sensor 26A for detecting access of hands into the paperdischarge tray 16 instead of the sensor 26 detecting whether or not theprint medium P is placed on the paper discharge tray 16, may beimplemented. In this case, the image forming apparatus 1 predictswhether or not the print medium P has been removed from the paperdischarge tray 16 based on a signal from the sensor 26A.

FIG. 6 is an explanation diagram for explaining a configuration in thevicinity of the paper discharge tray 16 of an image forming apparatus 1Aincluding the sensor 26A instead of the sensor 26. Since a configurationof the image forming apparatus 1A is the same as that of the imageforming apparatus 1 except for the sensor 26A, a detailed descriptionthereof will be omitted.

The sensor 26A is a sensor for detecting the access of hands to thepaper discharge tray 16. The sensor 26A includes a light source, anoptical system, and a light receiving element.

For example, the light source is a diode that emits light. For example,the light source emits infrared light. The optical system is a lens thatemits light from the light source. In addition, the optical systemfocuses an image of light, which comes from a predetermined detectionrange on a space, on the light receiving element. The light receivingelement is an element for converting the light into the electric signal.For example, the light receiving element is a photodiode havingsensitivity in an infrared wavelength range.

When an object exists in the detection range of the sensor 26A, lightemitted from the light source through the optical system is incident onthe object. Furthermore, a part of the light incident on the object isreflected on a surface of the object and incident on the optical system.The light incident on the optical system reflected on the surface of theobject is formed as an image on the light receiving element. The lightreceiving element generates a signal according to the light forming theimage. With this, when the object exists in the detection range, thesensor 26A supplies a signal indicating ON to the CPU 61, and when theobject does not exist in the detection range, the sensor 26A supplies asignal indicating OFF to the CPU 61.

The image forming apparatus 1A may include a plurality of the sensors26A. As described in FIG. 6, the plurality of the sensors 26A areprovided at positions through which a user's hand passes when it reachesthe paper discharge tray 16. More specifically, an opening unit 27Awhich is a space for taking out the print medium P from the paperdischarge tray 16 to the outside of the housing of the image formingapparatus 1A, is configured in the image forming apparatus 1A. In anexample of FIG. 6, the opening unit 27A is provided over from the frontsurface to the side surface of the housing of the image formingapparatus 1A in the vicinity of the paper discharge tray 16. When theprint medium P on the paper discharge tray 16 is taken out to theoutside of the housing of the image forming apparatus 1A, objects suchas hands pass through the opening unit 27A. The sensor 26A detectspresence or absence of the object passing through the opening unit 27A.With this, the sensors 26A detect presence or absence of the objectpassing through the space between the light sources and the lightreceiving elements in order to detect access of the object with respectto the paper discharge tray 16.

The CPU 61 determines that the print medium P has been removed from thepaper discharge tray 16 based on a signal from the sensors 26A. Forexample, when a user's hand is input into the paper discharge tray 16,it is predicted that a detected result of the sensors 26A is switchedfrom OFF to ON. In addition, when the user grips the print medium P onthe paper discharge tray 16 and pulls out his/her hand from the paperdischarge tray 16, it is predicted that the detected result of thesensor 26A is switched from ON to OFF. Therefore, when the detectedresult of the sensors 26A is switched from OFF to ON, and then thedetected result of the sensors 26A is switched from ON to OFF, the CPU61 determines that the print medium P on the paper discharge tray 16 isremoved.

When the plurality of sensors 26A are provided, the CPU 61 switches anyone of the signals from the plurality of sensors 26A from OFF to ON, andthen when signals from all the sensors 26A are OFF, the CPU 61determines that the print medium P on the paper discharge tray 16 isremoved.

When the print medium P is removed from the paper discharge tray 16, theCPU 61 determines whether or not the printing process has completedbased on the print data. When the print medium P is removed from thepaper discharge tray 16 and the printing process has not completed basedon the print data, the CPU 61 causes the warning to be output throughthe display unit 20 and/or the speaker 24.

According to this configuration as well, when the printing process basedon the print data has not completed, that is, the print medium P whichis not yet printed out exists, the image forming apparatus 1A can outputthe warning at the timing when the print medium P is manually removedfrom the paper discharge tray 16.

The image forming apparatus 1 can capture a two-dimensional region witha camera provided at a position facing the paper discharge tray 16without implementing the configuration such as the configuration of thesensor 26A described above and analyze the captured image, and therebymay be configured to detect the removal of the print medium P from thepaper discharge tray 16.

In addition, the image forming apparatus 1 in which each user performsthe determination in Act 23 of FIG. 5, may be configured. For example,the CPU 61 of the image forming apparatus 1 functions as a useridentification unit that performs a user identification process foridentifying the user who removes the print medium P. For example, theCPU 61 of the image forming apparatus 1 obtains a face image of the userby capturing the face of a neighboring user with the camera 23 (imagecapturing unit). In addition, the nonvolatile memory 64 stores inadvance a plurality of elements of identification information foridentifying users and face feature data corresponding to eachidentification information. The CPU 61 compares the obtained face imagewith the face feature data stored in the nonvolatile memory 64, andperforms a face authentication process for identifying a user in thevicinity of the image forming apparatus based on a compared result.

Furthermore, the CPU 61 determines whether or not the printing processbased on the print data input from a PC corresponding to a userspecified by the face authentication process has completed. According tosuch a configuration, even if the printing process based on the printdata from another user has not completed, if the printing process basedon the print data from the specified user, has completed, the imageforming apparatus 1 can be controlled so as not to output the warningwhen the print medium P is removed from the paper discharge tray 16.

The functions described in the above embodiments may be realized notonly by using hardware but also by loading a program including eachfunction using software into a computer. In addition, each function maybe configured by selecting software or hardware as appropriate.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the inventions. Indeed, the novel embodiments described hereinmay be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the embodimentsdescribed herein may be made without departing from the spirit of theinventions. The accompanying claims and their equivalents are intendedto cover such forms or modifications as would fall within the scope andspirit of the inventions.

What is claimed is:
 1. An image forming apparatus comprising: an imageforming unit configured to perform a printing process of forming animage on a print medium based on print data; a processor configured todetermine whether or not the printing process has completed based onremaining print data to be printed, when the print medium is removedfrom a paper discharge tray in which the print medium on which the imageis formed by the image forming unit is placed, and to cause a warning tobe output upon determining that the printing process has not completedbased on the remaining print data to be printed.
 2. The apparatusaccording to claim 1, wherein the remaining print data to be printed isgreater than zero.
 3. The apparatus according to claim 1, wherein theprocessor is further configured to determine that the printing processhas not completed if an operation of the image forming unit isinterrupted and the print medium is removed from the paper dischargetray.
 4. The apparatus according to claim 1, wherein the processor isconfigure, to perform a user identification process for identifying auser who removed the print medium from the paper discharge tray, whereinthe processor determines that the printing process has completed basedon whether or not the remaining print data to be printed is associatedwith the identified user.
 5. The apparatus according to claim 4, furthercomprising: an image capturing unit positioned near the paper dischargetray, wherein the processor is configured to compare a face imagecaptured by the image capturing unit with face feature data of aplurality of users to identify the user who removed the print mediumfrom the paper discharge tray.
 6. The apparatus according to claim 1,further comprising: a sensor positioned to detect whether or not theprint medium has been removed from the paper discharge tray, wherein theprocessor determines that the print medium has been removed from thepaper discharge tray based on a signal from the sensor.
 7. The apparatusaccording to claim 1, further comprising: a speaker through which thewarning is output as an audio warning.
 8. The apparatus according toclaim 1, further comprising: a display through which the warning isoutput as a visual warning.
 9. A method of operating an image formingapparatus having an image forming unit configured to perform a printingprocess of forming an image on a print medium based on print data, saidmethod comprising: discharging the print medium after the printingprocess a has been performed on the print medium based on the printdata; detecting whether or not the print medium has been removed from apaper discharge tray; determining whether or not the printing processhas completed based on remaining print data to be printed; and upondetecting that the print medium has been removed from the paperdischarge tray and determining that the printing process has notcompleted, outputting a warning.
 10. The method according to claim 9,wherein the remaining print data to be printed is greater than zero. 11.The method according to claim 9, further comprising: upon detecting thatan operation of the image forming unit has been interrupted, determiningthat the printing process has not completed.
 12. The method according toclaim 9, further comprising: performing a user identification processfor identifying a user who removed the print medium from the paperdischarge tray, wherein determining whether or not the printing processhas completed is based on whether or not the remaining print data to beprinted is associated with the identified user.
 13. The method accordingto claim 12, further comprising: capturing a face image of a userpositioned near the paper discharge tray; and comparing the capturedface image with face feature data of a plurality of users to identifythe user who removed the print medium from the paper discharge tray. 14.The method according to claim 9, wherein a sensor is positioned todetect whether or not the print medium has been removed from the paperdischarge tray, and detecting whether or not the print medium has beenremoved from the paper discharge tray is based on a signal from thesensor.
 15. The method according to claim 9, wherein the warning isoutput through a speaker as an audio warning.
 16. The method accordingto claim 9, wherein the warning is output through a display as a visualwarning.